I have a 98 sienna that has a bad flex pipe on the exhaust. Toyota wants $1500 for the part. I was wondering if anyone has a website where I can get it cheaper or if it can be welded in cuz the muffler shops are saying they don't think they can. It's leaking oil out the backside of the motor, about a quart every 300 miles. it's possibly a main seal or possibly a head gasket, does anyone know of any problems that it might be?

First, what do you mean "bad flex pipe"? Is it leaking?

Second, is there a specific location the oil leaks out?

fyi, i was able to replace the flex pipe with another piece, used a clamp and welded the other end, for 100$ problem solved.
as to the oil leak, its coming out the back side up by valve cover gasket. however, they were just replaced in december. Im replacing the pcv valve today, but i am suspicious sludge is causing it :mad: as there was considerable sludge build up when valve cover gaskets were done. it is building excessive oil pressure in the crank case, i am suspicious this is causing it to lead oil. any thoughts on that theory??

First, what do you mean "bad flex pipe"? Is it leaking?

Second, is there a specific location the oil leaks out?

its very difficult to see EXACTLY where its leaking, as its coming from back side of motor. you cant see any oil leaking when u look at it from the top. but jack it up and its covered the back side of engine, all the way up to the top.

fyi.
sludge IS part of issue here (starting to burn oil and smoke badly on startup) .. but main oil leak is from the rear main seal!!!! anyone else have any problems with rear main on this vehicle?